New fleet of Australian frigates to be built for missile defence in face of rogue threat

Australia's next fleet of navy frigates will be tailored to shoot down incoming missiles in a recognition of the growing threat posed by rogue regimes such as North Korea.

Prime Minister Malcolm Turnbull will announce on Tuesday that the nine "future frigates", which the government wants to start building in 2020, will be equipped with an ambitious combination of the US-made Aegis combat system meshed with locally made SAAB Australia technology.

While the frigates are primarily meant for anti-submarine warfare, the inclusion of Aegis will tilt the purpose towards air and missile defence in a clear signal of the government's growing concern about the threat of missiles.

"Recent events in our region have proven that Australia's future frigates must be equipped to defend Australia from the threat of medium and long-range missile attacks," Mr Turnbull said in written comments provided in advance of the announcement.

"This technology will enable the future frigates to engage missiles at long range."

The frigates will not provide a comprehensive missile shield across Australia. But according to Andrew Davies, a defence expert with the Australian Strategic Policy Institute, the latest Aegis system would allow the future frigates to operate with US and Japanese partners as a kind of defence network to provide some protection to specific targets in the region.

The combat system is the brains of a warship, allowing it to detect threats, pinpoint targets and fire weapons.

Aegis, made by US giant Lockheed Martin, will be meshed with a system made by SAAB Australia that can work closely with the ships' Australian-made radar and specialises in tackling shorter-range threats.

A simulator at Lockheed Martin's STELaRLab in Melbourne shows how an Aegis-equipped destroyer could help intercept an attack.

The combat system is estimated to make up about $3 billion of the total $35 billion cost of the frigate program.

Other future Australian warships will use the SAAB system which Defence Industry Minister Christopher Pyne said would bring about $1 billion worth of work to local industry.

A time exposure shows the launch of a US anti-missile THAAD missile.Credit:AP

Dr Davies said a so-called "co-operative engagement capability" would allow the frigates to act as eyes and ears to allied ships and vice versa. Defence Minister Marise Payne stressed that being able to work with allies was a key part of the program.

But Dr Davies said the frigates would need to be upgraded with longer-range interception missiles than those already planned if they are to shoot down intercontinental ballistic missiles - the kind that North Korea could use to threaten Australia. The Aegis system the frigates will use would be optimised for shorter-range missiles but could catch intercontinental range missiles in the early phase of their flight, meaning the ships would need to be stationed in the seas close to North Korea.

US and Japanese destroyers are already equipped with Aegis ballistic missile defence systems and the latest SM-3 missiles, and are critical in trying to intercept any nuclear missiles fired by North Korea if the current tensions deteriorate into conflict.

Dr Davies said the Aegis announcement signalled a prioritisation of missile defence in addition to anti-submarine warfare but added that "they are 7000 tonne ships and there's no reason they can't do both".

The government is already considering ship-based, ballistic missile-defence on the Air Warfare Destroyers, which will hit the water over the next couple of years but for which an upgrade is already planned over the next decade.

Beyond North Korea, the US and its allies are also concerned in the longer run about China's vast arsenal of ballistic missiles.